Apparatus for applying adhesive to carton blanks



June 4, 1963 R- MoKlM BROWNlNG 3,092,513

APPARATUS FOR APPLYING ADHESIVE TO CARTON BLANKS Filed Aug. 7, 1958 2 Sheets-Sheet 1 ATTO/PNN@ vl B Pq No 0L PHMMEEO wN/NG.

June 4, 1953 R. MCKIM BRowNlNG 3,092,513

APPARATUS FOR APPLYING ADHESIVE TO CARTON BLANKS Filed Aug. 7, 1958 2 Sheets-Sheet 2 AEV INVENTOR. EHNDOLPHMl//ME/Pow/w/va Array/verm' Unitedl States `Patent O 3,092,513 APPARATUS FOR APPLYING ADHESIVE TO CARTON BLANKS Randolph McKim Browning, Providence, RJ., assignor to St. Reg's Paper Company, New York, NX., a corporation of New York Filed Ang. 7, 1958, Ser. No. 753,816 6 Claims. (Cl. 11S-212) This invention relates to apparatus for applying adhesive to a succession of workpieces, such as box blanks, and more particularly to apparatus for applying at speeds not heretofore `attained pressure sensitive adhesive to such a `succession of box blanks, drying such adhesive and stacking the blanks.

One of the objects of the present invention is to provide -improved apparatus of the above character which ca n operate at ya speed not heretofore attained and which can `apply adhesive accurately to selected areas of la succession of box blanks.

Another object is to provide apparatus of this type for applying adhesive to a succession of box blanks in such a manner that the selected areas to which .the adhesive is applied are non-contiguous (not face-to-face) despite the stacking of fthe box blanks, and a-lso despite the fact that adhesive is applied yto both sides of the box blanks, and this prior to a primary folding over of the box blanks and while they are thus in their initial flattened condition.

A further object is to provide an -appanatus of this type for applying adhesive to opposite side surfaces of box blanks in such a manner that they are ystackable and the pressure sensitive adhesive areas on one side will not be facing or adjacent to pressure sensitive adhesive areas on the other side when the box blanks Iare stacked in their initially attened condition, -and also when the box blanks are stacked after having undergone such primary folding, that is, after they have been folded over into the customary flat two-layer condition preparatory to erecting same, at which time the opposite extremities of the initially ilat box blanks have been brought in contact rand joined, for example, by means of box tape.

The invention in one aspect thereof is constituted by a glue applicator apparatus having a pair of plate cylinders for applying adhesive to opposite sides of the box blank and having also a pair yof pressure roll means for coacting with respective of the plate cylinders. Each plate cylinder is provided with adhesive yapplicator pads or plates for engaging selected areas of 'the oncoming series of box blanks and applying `adhesive thereto to achieve the objectives aforementioned. Each of the plate cylinders is separated from its respective pressure roll means by a distance which is substantially equal to the thickness of the adhesive applicator pads and the thickness of the box blanks. The box blanks `are urged by suitable means, such as resilient guide lingers, toward their respective pressure roll means thereby to prevent premature striking of the box blanks by the adhesive applicator pads upon the plate cylinders. The plate cylinders and their respective pressure roll means are axially horizontal and operatively connected -whereby the plate cylinders rotate in a `direction opposite to the direction of movement of the box blanks. Thus the pressure roll means are rotated to move the box blanks in their normal direction through the applicator whereas the plate cylinders move in counterrotation thereto in one form of the apparatus. An yadhesive pickup `roll positioned `in a bath of the adhesive is situated adjacent tan adhesive transfer roll and peripherally in contact therewith, the transfer roll in turn being positioned for engaging the adhesive applicator pads upon its respective plate cylinder. The aforementioned glue applicator is employed in combina- 3995925 lli Fatented June 4, 1963 lCe tion with a pair of drier means, one which directs radiant heat upon the selected areas of the series of box blanks after they have received the adhesive by the aforementioned glue applicator, and also a device for moving the succession of box blanks through the Vair for air drying and known as an air drier. If desired, interposed between lthe radiant heat drier .and the air drier are suitable means known as a timer-feeder for receiving the succession of box -blanks from the radiant heat drier and delivering same into the air drier. The radiant heat drier, in one form of the apparatus, is constituted by `a series of electrical heating means adapted for directing electrical heat energy in selected tareas upon the succession of box blanks, namely, upon both sides thereof, there being suitable conveyor means, for example, including an asbestos A conveyor belt for moving the box blanks from the adhesive applicator land through the radiant heat drier and thence to the timer-feeder which is, as aforementioned, positioned between the radiant heat drier and the Iair drier. The timer-feeder device receives each of the box blanks and provides an impetus thereto for delivering or thrusting same into the air drier. The air drier, in one form, is constituted by a tower-like device which includes endless belt means, the longitudinal 'axis of which is vertical and supported by a suitable vertical towerJlike device, there being secured to the endless belt means a plurality of box blank carriers in the form of clamp-like devices (each comprising ya pair of parallel clamp ngers) adapted for opening yand receiving at la receiving station consecutively the box blanks delivered thereto by the timenfeeder device, and thereafter closing and holding the box blanks and moving same over the peak of the tower tand down to the base thereof to a discharge station where the clamping devices are automatically opened and the box blanks are discharged.

The above and further objects will more fully appear from the description set forth below when read in connection with the accompanying drawings, it being distinctly understood that the drawings are for purposes 'of illustration only and do not 'limit the definition of the invention, reference for this latter purpose being had to the appended claims.

In the drawings:

FIG. 1 is a side elevation, partially schematic, partly in section' and with parts 'broken away, of one form of apparatus embodying the invention;

. FIG. 2 is a plan view of the apparatus shown in FIG. 1, also partly in section and with parts broken away;

FIG. 3 is a fragmentary end view of a part of the aforementioned glue applicator, with parts broken away, and illustrating the action of guide fingers -for urging a workpiece toward a pressure roll and away from a plate cylinder;

FIG. 4 is an end View somewhat similar to FIG. 3 but With parts thereof in different operating positions;

FIG. 5 is an end view of certain of the parts shown in FIGS. 3 and 4 but Without the aforementioned guide iingers and illustrating the etfect of eliminating such guide fingers; fand FIG. 6 is a top view of a box blank showing a typical pattern of adhesive applied thereto and also representing the layout or development of the periphery of the upper plate cylinder and the location of the adhesive pads thereon.

Referring to the drawings in lgreater detail, and in particular to FIG. l, the apparatus consists of a pressure seni sitive glue applicator 20 which applies pressure sensitive adhesive to a succession of box blanks and delivers same to a drier 21 which, in the form shown, is of the socalled radiant heat variety directing radiant heat upon selected areas of the 'boxY blanks thereby to perform an initial drying action thereupon. The drier 21 delivers the succession of lbox blanks to a timer-feeder apparatus 22 which receives same and provides to each an impetus for delivering or shooting same into a succession of clamping devices, such as 23, which are mounted upon a iinal drier 24 known as an air drier. The drier 24, in the form shown,ris a tower-like structure substantially vertical in attitude and comprises anlendless belt means to which are secured the plurality of box blank clamping devices 23. The longitudinal axis of the endless belt means is thus substantially vertical and is supported by a tower-like structure 25 which move-s the box-like clamps 23 from a delivery station 26 to a discharge station Z7. Suitable means are provided for automatically opening and closing the arms of the clamps 23 at the receiving station 26 and at the discharge station 27. At the latter station suitable box blank stacking means are provided.

The pressure sensitive adhesive applicator 20, in the form shown, is designed to apply adhesive to both sides of corrugated box blanks at a speed of up to 175 blanks per minute. Such blanks, for example, may be of a size of 36 inches x 8O inches as a maximum, and a minimum of 16 inches x 24 inches. The thickness of the corrugated cardboard can be, for example, 3/32 up to ry/16 of an inch.

The pressure sensitive -glue applicator 20 includes in combination suitable automatic feeding means for the box blanks which are stackablev in a station 28 between stacking Walls 29' and 30. The latter wall 30` can be moved vertically to suit blank thickness so that the lowermost of the stacked box blanks is released onto a suitable grasping device for urging same into the adhesive applicator.

There are two adhesive applicator units generally designated 3l yand 32, respectively, for applying adhesive to the upper and lower surfaces of the box blanks in a desired pattern, such as that indicated, for example, in FIG. 6, which blanks also represent a layout or development of the peripheral surfaces of the plate cylinders which apply the adhesive as will appear below. The applicatorV units 31 'and 32 may employ such plate cylinders which, if desired, are similar to those of a so-called printer slotter. Applicator dies or pads of rubber, such as 33 land 34, respectively, are secured upon the peripheries of plate cylinders 35 and 36 by any suitable means, for example, by tape.

Suitable feed rolls 37 'and 38 are provided for feeding the blanks to the rst adhesive applicator unit 31, said feed rolls 37 and 38 having the axes thereof parallel, of course, to those of the plate cylinder 35, and the pressure rolls 39 which coact therewith. The feed roll 37 preferably has a rubber periphery or rubber rings mounted upon the periphery spaced thereon for obtaining a firm grip upon the box blanks at high speed. The feed roll 38 preferably is of steel and may be without such rubber rings.

An adhesive reservoir 40v is provided for containing the pressure sensitive adhesive and Vinwhich rotates the lower portion of the periphery of an adhesive pickup roll 41 which is in peripheral engagement with an adhesive transfer roll 42, the latter in turn being positioned in such a manner that it will come in peripheral engagement with lthe outer surfaces of such adhesive applicator pads as pad 33 aforementioned. Plate cylinder 35 and transfer roll 42 rotate in opposite directions in the form shown in FIG. l, the same being true of cylinder 36 and roll 49. Y

It will be noted in FIG. l that there are two pressure rolls 39 which coact with the plate cylinderV 3S. However, it is not necessary for two such pressure rolls to be employed, it being adequate to employ one in the manner shown' in FIGS. 3, 4 and 5, if desired.

v The pressure rolls39 lare spaced from the plate cylinder 3S in the manner explained above.

The pressure rolls 39' rotate in a clockwise direction (as viewed in FIG. ll) 'for the purpose of advancing the box blanks to the right, as viewed in this figure. However, the plate cylinder 35 rotates, in one form of the apparatus, also in a clockwise direct-ion and hence the adjacent but spaced apart portions of the peripheries of the plate cylinder 35 and the pressure rolls 39 are moving in opposite directions. This, of course, means that the lower portion of the periphery of the plate cylinder 35 is moving in a direction counter to the direction of movernent of the box blanks as they advance to the right in FIG. l. Although this occurs in one form of the apparatus, in another forml of the apparatus this characteristic is not employed, the .plate cylinder moving in a counterclockwise direction, its lower portion hence moving in the same direction as that of the advance of the box blanks.

The other applicator unit `32. is substantially identical to unit 31 except that it is positioned for applying adhesive to the lower surface of the box blanks as they go by, and such unit includes upper and lower feed rolls 43 and 44, respectively, the plate cylinder 36 and discharge rolls 45and 46. Pressure rol-ls L39a rotate in a counterclockwis'e direction whereby the lower portions of their peripheries move in the direction of box blank advance. -Plate cylinder 36 rotates in one form, also in a counter clockwise direction with the upper portion moving against the direction of box blank movement.

In another lform of ythe apparatus, the characteristic, whereby the lower portion of the periphery of plate cylinder 35 and the upper portion of periphery of plate cylinder 36 move in la direction counter to the direction of movement of the box blanks, is not employed. In form plate cylinder 35 rotates counterclockwise and plate cylinder 36 rotates clockwise (as viewed in FIG. l) thereby making the lower portion of the periphery of plate cylinder 35 and the upper portion ofthe periphery of plate cylinder 36 move in the same direction as that of the sbcx blanks.

The pressure sensitive adhesive is applied to the adhesive applicator pad, such as 34, by means substantially similarY to those described for the unit 31, namely, an adhesive reservoir 47 in which moves the lower portion of the periphery of an adhesive pickup roll 48 which is in peripheral engagement with an adhesive transfer roll 49, the latter in turn being situated for engaging the outer surface of the adhesive applicator pad, such as 34 above mentioned.

The adhesive rolls, that is, both the adhesive pickup and transfer rolls, preferably are made of steel and chromium plated. The plate cylinders 35 and 36 preferably are provided upon their peripheries with parallel longitudinally or axially extending lines, for example, thirty-six in number and about l'inch apart, to assist in the accurate location of the adhesive applicator pads. Suitable means are provided for the registering of such adhesive appl-icator pads (or glue plates) relative to the box blanks. That is, suitable means may be provided for axially shifting the plate cylinders 35 and -36 in such a Way that a desired adjustment of the various glue pads can be obtained, and also means are provided for angularly shifting each plate cylinder about its axis whereby relative adjusting angular movement can be effected for accomplishing the aforementioned registration of the adhesive applicator pads with the selected areas of the box blanks as they move past the adhesive applicator stations.

Referring now 'to the radiant heat drier 21, this unit or section preferably includes a plurality of infrared electrical heating elements. Box blanks are conveyed through this section preferably by means of heat resistant conveyors, such as an asbestos belt conveyor, and suitable means are provided for controlling the conveyor speed and hence the time to which the box blanks are subjected to the radiant heat. A suitable variable speed dri-ve 50 v may be employed for this purpose which is operatively connected to a belt pulley, such as 51, over which one of the aforementioned asbestos conveyor belts, such as 52,

can pass at the righthand extremity thereof, the lefthand extremity passing over a belt pulley 53. An upper belt 54 coacting with the belt 52 is shown passing respectively over pulleys 55 and 56.

In the radiant heat drier unit 21 there may be employed, for example, a total of eight elongated heating elements, each of which, for example, may be 16 feet long, there being four of such units situated above the path of the workpieces and four below for respectively heating the upper and lower surfaces of the workpieces. Each of such heating elements can be made up of four subelements which are situated in alignment which are mounted on suitable structural mernbers which may be adjusted in position into desired proximity and relative alignment and attitude to the 'adhesive on the succession of workpieces. Thus, if desired, suitable rollers may be employed for mounting the heating subelements to permit adjustable positioning thereof.

I have found it advantageous, in one form of the apparatus, to employ heating subelements each of which, for example, consume about 40 watts per square inch at 220 volts, 60 cycle, their total rat-ing being approximately 14,000 watts.

Shown in FIG. l are only two belts 52 and 54, howevr, in fact there are four belts employed, two being situated behind respectively the belts 52 and 54 and which cannot be seen in FIG. 1 for this reason. Each of such four belts is provided with individual means for accomplishing lateral adjustments of the position thereof to ensure that they properly engage the box blanks as they move through the radiant heat drier unit 21.

The principal purpose of the radiant heat drier section 21 is to dry along the adhesive line, and the length and heating element specifications vary in accordance with the chemical composition of the adhesive, the boxboard, and also the moisture content of the boxboard and other factors.

The timer-feeder device 22 receives the box blanks consecutively, as aforementioned, and shoots or throws same consecutively into the open clamps 23, one of which is positioned at the receiving station 26 (as in FIG. l) to receive each oncoming box blank. It is understood, of course, that each clamp 23' is open for this purpose at such receiving station.

Referring now to the air drier 24, the drier structure is preferably of tower-like conformation for the purpose of reducing the oor space required by the apparatus, and includes in combination a supporting tower device or structure 25 having suitable rollers 57 (at the peak) and 58 and 59 at the front and rear thereof respectively around which pass suitable endless belt means 60, such as sprocket chain means, which in turn supports the plurality of box blank clamps 23 while the blanks are undergoing drying in air while moving up to the peak of the tower and down t0 the discharge station 27.

The air drier tower, for example, may be of the order of 20 to 25 feet in height and the box blank clamp means may move at a rate corresponding to that of the other elements of the machine, for example, of the order of 100 box blanks or carriers per minute. With a height, for example, of about 23 feet and a rate of about 100 box blank carriers per minute, there is allowed a two minute drying time for a box blank between the time that is is grasped by the box blank clamping means at the receiving station 26 and discharged at the discharge station 27.

The driving means for such endless belt means which in turn support the box blank clamp devices is variable and is adjusted to be slightly ahead of the drive of the adhesive applicator unit 20, such relationship being accomplished by inspecting -an adhesive applicator tachometer 61 and an air drier tachometer 62 which are respectively operatively connected to their units.

The opening and the closing of the box blank carriers or clamps is accomplished on the periphery of the leading set of sprockets or chain tracks of the air drier 24. The

rear track or inclined portion 25a is set at an approximate 20 incline.

Preferably the timer-feeder 22 is driven directly by drive means for the air drier. In the form shown, such drive means for the air drier are constituted by a motor 63 which, by means of a belt 64, is drivably connected to a variable speed unit 65 which in turn is connected to a reduction gear device 66, the latter in turn by means of a chain or belt 67 directing driving power to the endless belt means 60 which in turn passes over the aforementioned rollers 57, 58 and 59. The reduction gear device 66, for example, by means of drive shaft 69, directs torque to the aforementioned timer-feeder 22 and to the variable speed unit 50 of the radiant heat drier 21.

In view of the fact that the timer-feeder 22 is driven directly from the air drier, the box blanks which arrive in front of the air drier to be delivered to the delivery station 26 and out of time, that is, either too early or too late, are picked up at a proper time and shot or urged between the open arms of clamps 23. The inner or clamping surfaces of arms 23a and 23h of each clamp 23 are formed with concave surfaces (as in FIG. 1) whereby each box blank rests on carriers on its longitudinal edges only whereby adhesive imprints are not smeared upon the inner surfaces of the arms and there is a separation between the inner surfaces of such arms and the workpieces.

Another function of the timer-feeder 22 is to cause an edge-to-edge running of the box blanks through the radiant heat drier and hence to achieve greater heat economy, the drier focusing or concentrating radiant heat energy along the adhesive lines.

Box blanks of differing sizes obviously have different weights and consequently the amount of force required to throw each different size box blank between a pair of carrier arms 23a, 23b is variable and must be regulated to suit the weight of the box blanks thereby to avoid damaging their edges. The timer-feederl device has suitable regulating means for adjusting the force thereof to the weight of the box blank.

At the aforementioned discharge station 27, if desired, a discharge conveyor (not shown) can be provided and upon which the box blanks can be deposited in shingle stacked -attitude and thus removed to a suitable location. Such take away conveyor is employed to carry each box blank out and away from the opened arms of the carriers 23, this being done automatically. Thus the take away conveyor preferably is a short one and is normally situated to deliver the box blanks onto a stacking skid loading conveyor, such as one used on printer slotters.

Referring to FIGS. 3, 4 .and 5, there will now be discussed the employment of guide lingers aforementioned for urging the workpieces toward pressure roll means.

Shown in FIG. 3 is an adhesive applicator unit for acting upon the bottom surface of a box blank and which corresponds to unit 32 with the exception that in lieu of a pair of pressure rolls, such as 39a shown in FIG. l, there is employed a single pressure roll 7 0 which is spaced from the periphery of a plate cylinder 71 which corresponds to plate cylinder 36. There is employed with this assembly a set of guide lingers or guide linger means '72 which urge each workpiece toward the pressure roll '70. Such guide fingers are also known as hold-down lingers and are for the purpose lof preventing so-called prestrikes of the adhesive applicator pads upon the workpieces, that is, for preventing premature strikes which otherwise would occur if the iworkpieces were permitted to sag or assume a position lower than that shown in FIG. 3. See FIG. 5.

The guide fingers 72, for example, ensure that a point such as 73 upon a workpiece 74 reaches point 75 contemporaneously with point 76 of an adhesive applicator pad 77, this being the predetermined and desired time of coaction of the pad 77 with the workpiece. Thus a premature striking of the Aadhesive is avoided.

pad upon the workpiece Sho-wn in RIG. y is-the effect of 'eliminating the guide fingers 72 whereby the lworkpiece 7dis permitted to Sag orto assume a relatively low position whereby the adhesive applicator pad 76 prematurely engages same and thus prematurely spreads adhesive upon the lower surface which constitutes a waste of the adhesive.

Thus the use of the guide fingers 72 accomplishes the relationship of the parts shown in FIG. 4 wherein there is a desired point of registration between the adhesive applicator pad 77 and the workpiece 74, that is, wherein the point 76 of the adhesive pad 77 contacts the point 73 of the workpiece '74 and accomplishes the desired application of adhesive thereto.

It is noted in FG. l that the two glue application units are so situated that adhesive is applied both to the top and bottom surfaces of each box blank during a single pass through the machine. Furthermore, with respect to the aforementioned counterrotation form of the invention wherein the plate cylinders move in -a direction opposite to the adjacent parts of their coacting pressure' rolls, the hold-down or guide ngers 72 ensure that each box blank is positioned against its respective backup roll at the time of contact between the adhesive applicator pad and the blank.

The above-mentioned adhesive applicator unit is adapted for applying adhesive to the box blanks in accordance with an invention described in U.S. Patent No. 2,874,891, issued Feb. 24, 1959, application Serial No. 606,075, relating to Pressure Sensitive Adhesive and Method of Applying Same to Cartons and Cases.

Referring again to FIGS. 3, 4 and 5, it will be noted that along the leading edge of the adhesive pad 77 there is situated a Iwedge 78 which is so disposed that it will prevent damage due to collision between the'leading edge the workpiece and the leading edge of the adhesive pad.A

However, it has been found advantageous to employ such wedge 78in addition to the finger 72.

For purposes of illustrating a development or rolloutof the peripheral surface of the plate cylinders 3S and 36, there is shown in FIG. 6 the top surface of a carton blank which is acted upon by the upper plate cylinder 35.

The plate cylinder 35 applies adhesive to the top surface of a carton or box blank79, as shown in FIG. 6, such top surface being designated 80.

The box blank 79, referring to FIG. 6, is of the type having four side wall sections S2, 83, S4 and 85, respectively, Nvhich are consecutively connected along the fold lines 86, 87 and 8S. That is, the side wall section 82 is connected to section 83 along the cornerV fold line 86, sections 83 and 84 along the corner fold line 87 and sections 84 and 85 along the fold line 88. Such fold'lines normally comprise score lines to facilitate the folding of the side wall sections.

Each of the side wall sections S2, S3, S4 and 85 have integrally connected thereto tongues or flaps which are foldable to produce a box in a well known manner. Thus the side wall section 32 along end fold lines i521: and 32b respectively has connected thereto llaps 82C and 82d. Analogously the side wall section 83, along end fold lines 83a and 83h has integrally connected thereto the flaps 83C and 83d. The other two side wall sections Srland 85 have analogous parts secured thereto bearing the designations shown (84C, 84d, 35o, 85d).

On the top surface S0, as aforementioned, adhesive is applied by means of the plate cylinder 35 over the areas 89 and 90 of the flap 83C and 91 and 92 of the ap 83d.

Also, adhesive is applied, as shown in PIG. 6, on the areas 93 and 94 ofthe ap 85C, and 95 and 96 of the hap' It will be noted that the blank 79, after having passed through a printer slotter, is provided with slots, such as 8 79a, 7917, separating the several tongues or flaps in lthe manner shown in FIG. 6.

Referring again to FIG. 6, the side wall section 82 on its bottom surface and by means of the lower plate cylinder 3:6 has adhesive applied a portion of the tongue 82C and a portion of the tongue '82a'. Such location of the adhesive-bearing areas thus is complementary with respect to analogous areas on the top surface 80 of the side wall section 82 whereby, in response to the stacking of the blanks 79, there will be no fa-to-face yareas bearing the pressure sensitive adhesive, at least with respect to the side wall section 8?2 and its two flaps 82C and 82d. Toward the latter purpose, the flaps l83e and 83d of the side wall section 83 (bottom surface) have no adhesive applied thereto thereby being complementary with respect to the adhesive lbearing areas 89, 90 and 91, 92.

The side Wall section 84 on its bottom side, on the other hand, has Iapplied thereto pressure sensitive adhesive on the ap 84C and the flap 84d, which areas in turn are complementary with respect to the top surfaces of such flaps in such a way that therewill vbe no face-to-face areas in response yto the stacking of the blanks in their initially flattened condition as shown in FIG. 6.

Analogously the bottom surfaces of the flaps 85C and 85d bear no adhesive in the form shown.

The plate cylinders 35 and 36 may have their peripheries formed, ormay have adhesive pads located thereon, in such a way that a single blank, such as 79, will receive the application of adhesive over the areas -89-96, inclusive, While passing through the machine one such box blank 79 at a time. And alternatively, the box blank 79 may =be passed through the machine or applicator 20 two at a time, .th-at is two ofthe blanks 79 may be connected along a side line thereof, namely, along the side line of the top-flaps (82c-8'5c), as viewed in IFIG. 6, and under such conditions the adhesive pads of the plate cylinder are constructed and arranged to apply the adhesive to accommodate such two box blanks While so connected.

'Ihe periphery of the lower plate cylinder 36 is constructed andV a-rranged in a manner analogous to that of the upper plate cylinder to apply the adhesive either to one blank 79 or ,-to `two blanks connected together in the manner last mentioned.. XIt is, of course, understood that if two blanks `are passed through the machine, they are later cut apart yalong such side line.

It will be noted with respect to PIG. 6, that when the Ibox blanks are folded over to form the primary foldedover condition for the purpose of making a hinge or manufacturers joint, there is no adhesive-to-adhesive contact between the ladjacent flap surfaces which, at this point, become inside flap surfaces by virtue of being inside the primarily folded-over box blank. That is, there is no 4face-to-face or -adhesive-to-adhesive contact between the upper and lower aps. However, when the box blank is erected and the aps are closed in the usual manner, there is a minimum of about 40% of `the flap area which is covered by the adhesive.

Referring again to HG. 6, there are shown the relative locati-ons of four heater lines 102, 103, 104 and 105 which` indicate, with respect to the box blank 79, the location of the elongated heater subelements in the radiant drier section 21 of Athe apparatus. Also, Aas shown in FIG. 6, are the relative locations of the conveyor belt lines a-t 106 and 107. The heater lines 1102-105, inclusive, are appli- 1cable to the blank top surface 80, it being understood that suitable heater lines 10S and 109 4are provided for the bottom Vsurface 81 of the box blank, such heater lines 108 4and 109 indicating the relative locations of heater subelements situa-ted below the box blank in the radiant heater Z. If desired, additional heater lines (eg. two) or subelements may be provided for acting on vthe bottoni surface.

There is thusV provided a novel apparatus which is capable of metering and applying adhesives to box blanks in the manner above set for-th and such adhesives include,

tion of rotation of the glue or adhesive rolls.

9 for example, pressure sensitive or pressure actuatable adhesives which contain, by way of example, 40% of natural rubber. The device is designed for application of such adhesive upon relatively =uneven, non-uniform surfaces, such as that of corrugated board used in the formation of cartons.

The apparatus is designed for the purpose of delivering a selected number of box blanks suitably coated with adhesive at a speed, for example, of l() blanks per minute, such speed being attainable -by the applicator 20. The production speed of the overall machine is a function of the time required to assure adequate drying. The drying time is a function of the uniform application of the adhesive and accordingly the production speeds of the apparatus as a Whole can be attained, for example, the aforementioned 100 blanks per minutes, by adjusting or selecting the drying capacity of the radiant drying section 21 to ensure that suitable initial drying is accomplished by means of this unit prior to the delivery of the blanks to the air drier.

There is thus provided a novel apparatus, particularly with respect to the arrangement yof the drive and the direc- Moreover, the disposition of the glue or adhesive application units 31 and 32 in relation to one another are advantageous whereby adhesive is applied both to the top and bottom of the box blank during a single pass through the applicator. Furthermore, with respect to the aforementioned counterrotation concept, namely, wherein the periphery of the plate cylinder where it engages a box blank moves in a direction opposite to the direction `of motion of such blank, the use of the hold-down fingers or guide fingers 72 is particularly advantageous to ensure that each box blank is positioned against its respective backup roll or pressure roll means at the time of contact between the plate cylinder and the blank.

What is claimed is:

1. Apparatus for applying liquified adhesive to boxboard blanks comprising a plate cylinder having an adhesive applicator pad secured to the periphery thereof and protruding therefrom along only a portion of such periphery, means for applying such adhesive to said adhesive applicator pad for subsequent transfer to such blanks, a pressure roll parallel to and spaced from said plate cylinder for receiving such blanks therebetween, the spacing between said plate cylinder and said pressure roll providing tangential engagement of such blanks by said pressure roll and by said adhesive applicator pad, means for feeding such blanks between said plate cylinder and pressure roll at a predetermined speed, means providing rotation of said pressure roll at a peripheral speed substantially equal to and in the same Vdirection as said speed of such blanks, means rotating said plate cylinder producing a significant speed differential between the peripheral speed of said adhesive applicator pad and ysaid speed of such blanks, and resilient guide finger means urging such blanks into said tangential engagement with said pressure roll and away from said tangential engagement with said adhesive applicator pad.

2. Apparatus for applying liquified adhesive to boxboard blanks according to claim l, wherein the direction of movement of said adhesive applicator pad is opposite to the direction of movement of such blanks at the location of their said tangential engagement, and said adhesive applicator pad has wedge means at the leading edge thereof to prevent colliding with and crumpling of the leading edges of the oncoming box blanks.

3. In apparatus of the class described, an adhesive applicator, including a first plate cylinder and finst pressure roll means, said plate cylinder and roll means having parallel axes and the peripheries thereof being in selected spaced relationship for receiving therebetween a succession of oncoming box blanks, said plate cylinder having adhesive applicator pads secured to the periphery thereof for directly Iapplying adhesive to selected areas of one side of such succession of box blanks; means for applying such yadhesive to said adhesive pads including an adhesive reservoir, an adhesive roll and an adhesive transfer roll positioned for engaging said adhesive pads; means for feeding the box blanks between said plate cylinder and pressure roll means, a second plate cylinder and second pressure roll means for receiving therebetween `after discharge by the first plate cylinder and pressure roll means the succession of box blanks for the application of adhesive directly to selected areas of the other side of said box blanks, said second plate cylinder having adhesive pads secured thereto, means for applying adhesive to the adhesive pads upon said second plate cylinder, which means are similar to that above defined; first and second sets of resilient guide fingers positioned respectively for coacting with said first and second pressure roll means for resiliently urging the succession of box blanks toward the respective pressure roll means and away from the respective plate cylinders; and means for operatively interconnecting each of said plate cylinders with its respective pressure roll means for rotation in opposite directions and for movement of said pads of said plate cylinders in a direction opposite to the direction of motion of the box blanks, and means for driving said roll means and cylinders, the distance between the periphery of each of such pressure roll means and its respective plate cylinder being substantially equal to the thickness of a box blank `and the thickness of an adhesive applicator pad, said guide fingers functioning to prevent movement of the box blanks out of a selected path and toward the plate cylinders whereby premature engagement between pads and blanks otherwise might occur.

4. In apparatus of the class described, an 'adhesive applicator, including a first plate cylinder and first pressure roll means, said plate cylinder and roll means having parallel axes `and the peripheries thereof being in selected spaced relationship for receiving therebetween a succession of oncoming box blanks, said plate cylinder having adhesive applicator pads secured -to the periphery thereof for directly applying a pressure sensitive yadhesive in a liquid vehicle to selected areas of such succession of box blanks; means for applying Isuch adhesive to said adhesive pads including an Iadhesive reservoir, an adhesive roll and an adhesive transfer roll positioned for engaging said adhesive pads; means for feeding the box blanks between said plate cylinder land pressure roll means, a second plate cylinder and second pressure roll means Ifor receiving therebetween after discharge by the first plate cylinder and pressure roll means the succession of box blanks for the application of `adhesive directly to selected areas of the other side of said box blanks, said second plate cylinder having adhesive pads secured lthereto, means for applying adhesive to the yadhesive pads upon said second plate cylinder, which means are similar to that labove defined; first and `second sets of guide fingers positioned respectively for coacting with said first and second pressure roll means for urging the succession of box blanks toward the respective pressure roll means and away from ythe respective plate cylinders; `and means for operatively interconnecting each of said plate cylinders with its respective pressure roll means for rotation in opposite directions and for movement of said pads in -a direction opposite to that of said box blanks, and means for driving said roll means 'and cylinders, the distance between the periphery of each of such pressure roll means and its respective plate cylinder being substantially equal to `the lthickness of a box blank and the lthickness of an adhesive applicator pad, said guide fingers functioning to ensure .that the adhesive yapplica-tor pads engage the selected areas of the box blanks in an accurate manner and free of premature engagement.

5. Apparatus in accordance with claim 4 wherein selected of said adhesive pads are provided with wedge means at the leading edges thereof to prevent colliding 1 1` with and -crumpling ofthe leading edges of the Voncoming box blanks.

6. In apparatus of the class described, the combination including: Van applicator for applying adhesive to selected areas of a series of box blanks, such adhesive applicator including in combination means for feeding box blanks consecutively into said applicator, a plate cylinder mounting a plurality of adhesive applicator pads, pressure roll means for coacting with said plate cylinder and positioned for receiving in the bite therebetween the succession of lbox blanks whereby the adhesive is applied to the aforementioned selected areas of the blanks, a reservoir for such adhesive, means for transferring such adhesive trom the reservoir to the aforementioned adhesive -applicator pads on said plate cylinder, saidiirs't-mentioned plate cylinder being situated for applying the adhesive to the aforementioned selected areas on one side of each box blank; feed roll means interposed between said box blank feeding means and said plate cylinder for receiving the box blanks and urging same between said plate cylinder and pressure rolls means, said plate `cylinder and pressure roll means being spaced apart land thus free of peripheral Contact and being mounted with their axes parallel, the spacing between .the periphery of the adhesive pads and the periphery of the pressure roll means being substantially equal to the thickness of la box blank, means for rotating said plate cylinder and pressure -roll means in opposite directions and for movement of said pads in -a direction opposite to that of said box blanks, and means for driving said roll means and cylinders, guide iingers for urging the succession of box blanks toward engagement 12 with the periphery of the pressure roll means and away from peripheral engagement with lthe plate cylinder; and a second assembly of means for applying adhesive 'to selected `areas of the other side `of the 'box blank, such assembly being substantially similar to that defined heretofore, such second Vassembly of adhesive applying means being 4situated adjacent to but spaced from the rst adhesive applicator means whereby the -box 4blanks can receive adhesive on both sides during the single pass through the apparatus.

References Cited in the file of this patent UNITED STATES PATENTS 603,075 Compton Apr. 26, 1898 1,295,820 Watkins Feb. 25, 1919 1,815,372 Frazier July 21, 1931 1,926,363 Bergstein Sept. 12, 1933 1,936,286 Bradner Nov. 21, 1933 2,000,325 Ford et al. May 7, 1935 2,276,997 Richardson Mar. 17, 1942 2,291,097 Mooney July 28, 1942 2,549,000 Palmer Apr. 17, 1951 2,659,340 Zinn Nov. 17, 1953 2,726,174 Friel et al. Dec. 6, 1955 2,748,025 Sackett et 4al May 29, 1956 2,875,726 Anness Mar. 3, 1959 2,951,700 Huber Sept. 6, 1960 FOREIGN PATENTS 736,179 Great Britain Sept. 7, 1955 

1. APPARATUS FOR APPLYING LIQUFIED ADHESIVE TO BOXBOARD BLANKS COMPRISING A PLATE CYLINDER HAVING AN ADHESIVE APPLICATOR PAD SECURED TO THE PERIPHERY THEREOF AND PROTRUDING THEREFROM ALONG ONLY A PORTION OF SUCH PERPHERY, MEANS FOR APPLYING SUCH ADHESIVE TO SAID ADHESIVE APPLICATOR PAD FOR SUBSEQUENT TRANSFER TO SUCH BLANKS, A PRESSURE ROLL PARALLEL TO AND SPACED FROM SIAD PLATE CYLINDER FOR RECEIVING SUCH BLANKS THEREBETWEEN, THE SPACING BETWEEN SAID PLATE CYLINDER AND SAID PRESSURE ROLL PROVIDING TANGENTIAL ENGAGEMENT OF SUCH BLANKS BY SAID PRESSURE ROLL AND BU SAID ADHESIVE APPLICATOR PAD, MEANS FOR FEEDING SUCH BLANKS BETWEEN SAID PLATE SYLINDER AND PRESSURE ROLL AT A PREDETERMINED SPEED, MEANS PROVIDING ROTATION OF SAID PRESSURE ROLL AT A PERIPHERAL SPEED SUBSTANTIALLY EQUAL TO AND IN THE SAME DIRECTION AS SAID SPEED OF SUCH BLANKS, MEANS ROTATING SAID PLATE CYLINDER PRODUCING A SIGNIFICANT SPEED DIFFERENTIAL BETWEEN THE PERIPHERAL SPEED OF SAID ADHESIVE APPLICATOR PAD AND SAID SPEED OF SUCH BLANKS AND RESILIENT GUIDE FINGER MEANS URGING SUCH BLANKS INTO SAID TANGENTIAL ENGAGEMENT WITH SAID PRESSURE ROLL AND AWAY FROM SAID TANGENTIAL ENGAGEMENT WITH SAID ADHESIVE APPLICATOR PAD. 